Fluid filter assembly having a combination valve

ABSTRACT

A filter assembly has a housing open at one end, with an annular filter media/core assembly disposed in the housing. An end plate having at least two inlet openings and an outlet opening is disposed in the open end of the housing. The end plate is affixed to a lid which is secured to the end of the housing. A combination valve is retained between the filter media/core assembly and the end plate. The combination valve has a first portion that cooperates with the first inlet opening in the end plate and a second portion cooperating with the second inlet opening. In use fluid will pass through the first inlet opening, the filter media/core assembly and be discharged from the housing through the outlet opening. When the filter media begins to clog, pressure will build and upon attainment of a predetermined pressure the second portion will open the second inlet opening and fluid flow can pass through the second inlet opening to the outlet opening, for discharge from the filter assembly and return to the engine, thereby bypassing the filter media. A spring is disposed between the end of the filter media remote from the end plate and the housing for biasing the filter media/core assembly toward the end plate to retain the combination valve in place.

RELATED APPLICATION

This application is a continuation in part of application Ser. No.10/715,682 filed Nov. 13, 2003

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention pertains to a fluid filter assembly having a combinationvalve retained between a filter media/core assembly and an end plateand, more particularly, to a fluid filter assembly having a novelunitary combination check valve and bypass valve cooperating with aunique end plate for controlling the flow of fluid into and out from thefluid filter assembly. Further, the invention pertains to a fluid filterassembly that includes a filter means that cooperates with a novelcombination valve and end plate and results in an overall design thatcan be more easily assembled.

2. Description of Related Art

There is known in the prior art a filter device having a housing with anopen end, a filter element received in the housing, an end plate closingthe open end and having inlet and outlet openings therein, and a valvefor cooperating with the inlet openings to allow oil to flow into thefilter through the inlet openings, but prevents flow of oil in a reversedirection. An example may be seen in Minowa et al. U.S. Pat. No.6,595,372. Prior filters are known that include a combination valvehaving two portions, the first portion for closing the inlet openings toblock the flow of oil back out of the inlet openings when the oil is notbeing circulated and the second portion for opening a bypass openingwhen the filter media is clogged for returning oil to the engine to keepthe engine lubricated even though the filter element is clogged. Anexample of such construction is Covington U.S. Pat. No. 5,405,527.

The present invention improves upon the filter with combination valve,shown for example, in the Covington U.S. Pat. No. 5,405,527 andovercomes disadvantages and deficiencies of such prior artconstructions.

SUMMARY OF THE INVENTION

An object of the present invention is to provide an improved filterassembly that has a simpler design and fewer parts than prior art filterassemblies.

Another object of the present invention is to provide an improved filterassembly that eliminates separate adhesives in fabricating the filtermedia and wherein internal element leakage is eliminated.

Yet another object of the present invention is to provide an improvedfilter assembly having a housing and a combination valve in the housingthat better tolerates heavily contaminated oil and is retained inposition against an end plate in the housing by the filter media underbias from an internal spring member between the top of the filter mediaand the interior of the housing of the filter assembly.

Another object of the present invention is to provide an improved filterassembly wherein parts are standardized for automated assembly and byincreasing or decreasing the length of the filter media, and thehousing, the capacity can be changed.

A still further object of the present invention is to provide an endplate having a single row of holes and flow channels formed in the endplate, each flow channel communicating at one end with one of the holes.

Other objects and advantages of the present invention will become moreapparent hereinafter.

The invention pertains to a filter assembly having a housing open at oneend, with an annular filter media/core assembly disposed in the housing.The end plate has at least one inlet opening, at least one bypassopening, and an outlet opening therein. The bypass opening comprises aflow channel formed in the end plate and communicating at one end withthe first inlet opening. A combination valve is disposed and retainedbetween the filter media/core assembly and the end plate. Thecombination valve has a first portion cooperating with the first inletopening in the end plate and a second portion cooperating with the flowchannel of the bypass opening. In normal operation the first portion ofthe combination valve will yield before the second portion of thecombination valve and fluid flow will pass through the first inletopening, the filter element and then be discharged through the outletopening. When the filter element begins to clog, pressure upstream ofthe first portion will build and upon attainment of a predeterminedpressure, the second portion will open the bypass opening and fluid flowcan pass through the bypass opening and out the outlet opening, therebybypassing the filter media/core assembly. A spring disposed between theend of the filter media/core assembly remote from the end plate and thehousing biases the filter element toward the end plate to retain thecombination valve in place and to seal fluid flow from between thecombination valve and the filter media and between the combination valveand the end plate. The filter media/core assembly, which is fabricatedfrom recyclable materials, includes top and bottom end caps which aresuitably bonded to the filter media.

BRIEF DESCRIPTION OF THE DRAWING

There is shown in the attached drawing a presently preferred embodimentof the present invention wherein like numerals in the various viewsrefer to like elements and wherein:

FIG. 1 is a side view of the filter assembly of the present invention,with part of the housing broken away to show interior parts includingthe combination check and bypass valve;

FIG. 2 is a plan view of the end plate of FIG. 1;

FIG. 3 is a cross-sectional view of the end plate taken generally alongthe line 3-3 of FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION

There is shown in FIG. 1 a filter assembly embodying the presentinvention. The filter assembly 10 includes a generally cup-shapedcylindrical shell or housing 12 that is open at one end and closed atthe other. Disposed within the housing 10 is an annular filtermedia/core assembly or filter means 15 which comprises an annular filterelement 14 mounted on a core 16. Provided in the open end of the housing10 is an end plate 18, which has a lid 20 secured thereto. An annular,resilient gasket 22 is received and retained in a recess in the lid 20for providing a seal between the filter assembly 10 and the engine block(not shown) to which the filter assembly 10 is secured in normal use.Recesses 13 are provided in the housing 12 proximate the top thereof forproviding a better gripping surface for a wrench used to assemble aclean filter assembly to an engine block and to remove a dirty filterassembly from an engine block for replacement.

Resilient means 24, for example, a spring, is provided between the topof the filter means 15 and the interior of the housing 12 for biasingthe filter means 15 toward the end plate 18.

The end plate 18 is best shown in FIGS. 2 and 3. The end plate 18 has atransverse section 29, an inclined section 31 inclined with respect tothe longitudinal axis of the housing and a transverse surface 33transverse to the longitudinal axis of the housing. Stated somewhatdifferently, the section 31 is inclined with respect to the central axisof the end plate 18 and the sections 29 and 33 are transverse to thecentral axis of the end plate 18. First inlet openings 30 are disposedin the inclined section 31 and second inlet openings 32 are disposed atleast in part in the transverse section 33. The first inlet openings 30are essentially circular bores or holes through the end plate 18. Thesecond inlet openings 32 are shown in the form of flow channels in theend plate 18 that communicate at one end with the first inlet openings30. The flow channels are preferably in the form of recesses formed inthe surface of the end plate 18 facing upwardly as viewed in FIG. 1, orfacing toward the annular filter media/core assembly 15.

The end plate 18 may be stamped so as to form depressions 37 on onesurface and complementary projections 39 extending from the oppositesurface. While eight depressions 37 are shown in FIG. 2, other numbersof depressions may be employed. The projections 39 are adapted to engagethe lid 20 and facilitate affixation of the lid 20 to the end plate 18.

The combination valve 26, which is retained between the lower end of thefilter element 14 and the top of the end plate 18 includes a firstportion 28 for controlling flow through the first inlet opening oropenings 30 and a second portion 32 for controlling flow through thesecond inlet opening or openings 34. The first portion 28 is moreresilient than the second portion 32 and will open under a lesserpressure, whereas the second portion 32 is stiffer and requires a higherpressure to open same. In a presently preferred embodiment of theinvention, the first portion 28 of the combination valve 26 will openthe first inlet openings at a minimum opening pressure, for example, onthe order of 1 psi and the second portion 32 will open the second inletopenings 34 at a predetermined higher pressure, for example on the orderof 8-10 psi. Provided centrally in the end plate 18 is a centralthreaded outlet opening 36. As seen in FIG. 2, the outlet opening 36 isabout the longitudinal axis of the filter assembly 10 and is within thecircle of second openings 34. In a presently preferred embodiment of theinvention as shown in FIG. 2, there are eight first inlet openings 30and eight second inlet openings 34 in the end plate 18. Other openingconfigurations than round are feasible and the number of openings can bevaried as will be apparent to persons skilled in the art, depending uponthe application for the filter assembly 10.

The combination valve 26 of the present invention includes a firstportion 28 that is annular and has a bend intermediate the radial extentof the first portion 28. The part of the first portion 28 that engagesthe second portion 32 extends generally horizontally and the free end isinclined outwardly and downwardly from the horizontal portion. Thesecond portion 32 includes an annular inwardly inclined part that isadapted to cooperate with the second inlet openings 34 and an upwardlyextending part 38 that cooperates with the horizontal part of the firstportion 28 to form a shoulder 40 that receives the lower inner end ofthe core 16 of the filter means. The part 38 is annular and engages theinterior of the lower end of the core 16 of the filter means whenassembled

The end plate 18 is suitably secured to the lid 20, for example, bywelding. The recess 42 in the lid 20 is adapted to receive and retainthe gasket 22 (FIG. 1). The lid 20 may be provided with projections (notshown) that slightly interfere with the recess 42, whereby in use, thegasket 22 is forced into the recess 42 and retained in place by thepressure from the projections engaging and cooperating with theresilient gasket 22.

The resilient gasket 22 will be retained in the recess or groove 42during handling of the filter assembly 10 and the projections definecooperative engaging means for holding the gasket in place. Personsskilled in the art will understand that the gasket 22 can be similarlyretained in place in the recess 42 if the projections on the lid 20 wereeliminated and projections were provided on the outside or insidesurfaces of the gasket 22 for engaging with the walls of the recess 42.Such arrangement would function in an equivalent manner.

Openings 30 are disposed in a circle generally concentric to the centralaxis of the end plate 18. The openings 30 are in the angled or inclinedportion 31 of the end plate 18 and the axis of each of the openings 30is inclined with respect to the central axis of the end plate 18 (andthe longitudinal axis of the filter assembly 10. Openings 32 aredisposed in the surface of the end plate 18 and each communicates at oneend with an opening 30.

The filter element 14 may be a conventional pleated filter mediacomprised, for example, of cellulose with some polyester. The core 16,which may be molded from an appropriate material, for example, a glassfilled plastic, such as, Nylon, is perforated so as to permit fluid flowthere through in use. Essentially, the core 16 comprises a cage formedby vertically disposed members 16 a suitably secured to horizontallydisposed members 16 b. The filter media is formed from a sheet ofpleated material joined along the facing ends by a suitable adhesive toform an annular sleeve on the cage 16. At the top and bottom aredisposed end caps 50 and 52, respectively. The end caps 50 and 52 may befabricated from a suitable composite material, for example acellulose/polyester composite. Preferably, the end caps 50 and 52 arebonded to the filter media 14, for example, by ultrasonic welding, toform a seal between the ends of the filter media and the end caps toprevent fluid flow between these elements in use. Essentially thematerials for the filter media 14, the core 16, and the end caps 50 and52 are compatible for ultrasonic welding to fuse the parts to oneanother. This process eliminates the need for adhesive and the ovencuring that was done in the past.

The top end cap 50 is a generally annular plate that has an opening 54in the center thereof. The bottom end cap 52 is a generally annularplate that has an opening 55 in the center thereof and projections (notshown) extending from the periphery thereof. Reference may be made toco-pending Ser. No. 10/715,682 for further details of the projections.The projections are adapted to abut the interior of the housing 12 tofacilitate assembly of the filter means into the housing 12 and toproperly position the lower portion of the filter means in the housing12. The recesses 13 in the housing 12 will normally engage the top endcap 50 and help to properly position the upper end of the filter meansin the housing 12.

The spring 24, which is disposed between the top of the filter element14 and the interior of the housing 12 is imperforate and thereforecloses the top opening 54 in the filter means, i.e., the opening 54 inthe top end cap 50 of the filter means. The spring 24 includes a centralimperforate dome-like portion 60 having a flattened bottom 62. Thedome-like portion 60 will engage in the opening 54 in the top end cap 50and close the opening 54 when the filter means 15 is assembled in thehousing 12. The spring 24 includes two spring arm portions that extendfrom the dome-like portion 60 and engage with the interior of thehousing 12 to apply a downward biasing force to the filter means. Onlyone arm 68 is shown in FIG. 1. Reference may be made to co-pendingapplication Ser. No. 10/715,682 for further details of the spring 24.

A seal 65 is provided on the upper end of the annular filter media/coreassembly 15 as seen in FIG. 1 to seal between the annular filtermedia/core assembly 15 and the spring 24. The seal 65 is made from asuitable material that is resilient, such as felt or a syntheticplastic. A similar seal 67 is provided on the lower end of the annularfilter media/core assembly 15 to help seal between the annular filtermedia/core assembly 15 and the combination valve 26.

The assembly of the filter assembly 10 will now be described. The filtermeans is assembled with the annular filter media 14 on the core 16 andthe end caps 50 and 52 secured in place. The end plate 18 and the lid 20are secured together, for example, by welding, and the gasket 22 ispositioned and retained in the recess 42 of the lid. The spring 24 isfirst inserted into the open end of the housing 12 until it seatsagainst the closed end of the housing 12. The filter media is positionedin the housing abutting the spring 24. The recesses in the housing 12will help to properly position the top of the filter means in thehousing 12 and the projections on the lower end cap will help toposition the lower end of the filter means in the housing 12. Thecombination valve 26 is positioned in the core 16 with the part 38engaging the inner surface of the core 16 to help seal fluid flowbetween the combination valve 26 and the core 16 of the filter means.The end plate 18 is inserted to close the open end of the housing 12 andthe outer rim of the lid 20 is rolled with the open end of the housing12 to form a seal 80. Positioning of the end plate 18 in the housing 12partially compresses the spring 24, whereby, when the parts areassembled a spring force is applied to the top of the filter meansurging the filter means toward the end plate 18. The spring force willhelp to clamp the combination valve 26 between the filter means 15 andthe end plate 18 and to seal flow from between the filter means 15 andthe end plate 18. The core 16 will firmly engage the part 38 of thecombination valve 26 and will also engage and bear upon the generallyhorizontal region of the first portion 28 of the combination valve 26.

In operation, the filter assembly 10 is spun onto a stud on the engineblock which engages the threads in the central opening 36 in the endplate 18 and is secured in place. The gasket 22 will engage the engineblock and preclude fluid flow from between the engine block and thefilter assembly 10. When the engine is started, fluid, usually oil, willenter the filter assembly through the openings 30. Slight pressure willmove the first portion or check valve portion 28 of the combinationvalve 26 away from the openings 30 and oil will flow through openings30, the filter media 14 and be discharged through the cental outletopening 36 for return to the engine. When the engine is turned off, thefirst portion or check valve portion 28 of the combination valve 26 willclose the openings 30 and prevent return of oil in the filter assembly10 to the engine. As the filter media 14 clogs during normal operation,pressure will build within the housing 12 of the filter assembly 10 andupon attainment of a predetermined pressure, on the order of 8-10 psifor one present application, the second portion or bypass portion 32 ofthe combination valve 26 will open and permit oil to flow through theopenings 34 and back to the engine, thereby bypassing the filter media14. Stated somewhat differently, during periods of time when highdifferential pressure exists across the filter media, due to cold thickoil or high contaminant loading of the filter media, the oil will gothrough the inner circle of openings 34 and open the second portion 32of the combination valve 26 to permit oil to bypass the filter media 14and exit the filter assembly 10 through the outlet opening 36 for returnto the engine.

The present invention materially reduces the number of parts needed fora line of filters. Presently standard automotive filter assemblies aregrouped into multiple filter diameters. A main line of filter assembliesheretofore consisted of multiple core diameters and multiple coreheights. With the present invention, filter sizes can be consolidatedand the complexity of internal components can be reduced significantly,for example to one core diameter and two core heights. Fabrication andassembly of the filter assemblies are simplified and can easily beautomated. The filter media, core and end caps are non-metallic and canbe easily recycled. The unique end cap design and orientation of theopenings therein is a facilitating factor in both construction andoperation of the filter assembly. The construction of the combinationcheck valve and bypass valve and the cooperation of the combinationcheck valve and bypass valve with the end plate contribute to easierassembly and enhanced performance. The respective circles of openings inthe end plate are fairly close to one another. The combination valve isconstructed so that it can be retained in place against the end plate bythe annular filter media/core assembly of the filter means. Tolerancesneed not be tight to obtain the sealing results desired.

While a presently preferred embodiment of the present invention has beenshown and described, it will be apparent to persons skilled in the artthat the invention may be otherwise embodied within the scope of thefollowing claims.

1. A filter assembly having a housing open at one end an annular filtermedia/core assembly disposed in said housing, an end plate secured tothe housing and closing the open end thereof, the end plate having firstinlet opening means, second inlet opening means and outlet openingmeans, the second inlet opening means comprising at least one flowchannel formed in the end plate and communicating at one end with thefirst inlet opening means, a combination valve disposed between theannular filter media/core assembly and the end plate for controllingfluid flow through the first inlet opening means and the second inletopening means, the combination valve including a first portioncooperating with the first inlet opening means and a second portioncooperating with the second inlet opening means, the second portionhaving more resistance to fluid flow than the first portion, whereby, innormal operation, the first portion will yield prior to the secondportion and fluid flow will pass through the first inlet opening means,the annular filter media/core assembly and then be discharged throughsaid outlet opening means and when the annular filter media/coreassembly begins to clog, pressure upstream of the first portion willbuild and upon attainment of a predetermined pressure, the secondportion will open the second inlet opening means and fluid flow can passthrough the second inlet opening means and out the outlet opening meansbypassing the annular filter media/core assembly.
 2. A filter assemblyas in claim 1, wherein the flow channel is a recess in the surface ofthe end plate facing the annular filter media/core assembly.
 3. A filterassembly as in claim 1, wherein the combination valve comprises anannular member, with the first portion extending outwardly from acentral portion and the second portion extending inwardly from thecentral portion, the second portion being stiffer than the firstportion; the annular filter element engaging the central portion of thecombination valve between the first portion and the second portion toretain the combination valve in place.
 4. A filter assembly as in claim1, wherein the end plate has an inclined portion inclined with respectto the longitudinal axis of the housing and a transverse portiontransverse to the longitudinal axis of the housing, the first inletopening means being disposed in the inclined portion and the secondinlet opening means being disposed at least in part in the transverseportion.
 5. A filter assembly as in claim 1, wherein the first inletopening means comprises a plurality of openings.
 6. A filter assembly asin claim 1, wherein the second inlet opening means comprises a pluralityof openings.
 7. A filter assembly as in claim 1, wherein the first inletopening means are comprised of a plurality of openings arrangedconcentrically around the axis of the filter assembly, and the annularfilter/media core assembly bearing upon the combination valve to retainsame in position against the end plate.
 8. A filter assembly as in claim3, wherein the second portion has a surface engaging the end plate and asurface engaging the central core.
 9. A filter assembly as in claim 1,wherein the flow channel is formed in the surface of the end plate. 10.In a filter assembly having a housing open at one end, an annular filtermedia/core assembly disposed in said housing, and an end plate securedto the housing in the open end and closing the open end, an end platehaving first inlet openings, second inlet openings and an outletopening, and a combination valve disposed between the annular filtermedia/core assembly and the end plate for controlling fluid flow throughthe first and second inlet openings, the combination valve including afirst portion cooperating with the first inlet openings and a secondportion cooperating with the second inlet openings, the second portionhaving more resistance to fluid flow than the first portion, whereby inoperation, the first portion will yield in response to minimum pressureand fluid flow will pass through the first inlet openings, the annularfilter media/core assembly and then be discharged through the outletopening and when the annular filter media/core assembly begins to clog,pressure will begin to build and upon attainment of a higherpredetermined pressure, the second portion will open the second inletopenings and fluid flow can pass through the second inlet openings andout the outlet opening bypassing the annular filter media/core assembly,the improvement comprising the second inlet openings being defined byflow channels in the end plate, each flow channel communicating at oneend to a first inlet opening.
 11. A filter assembly as in claim 10,wherein the flow channel is formed as a recess in the surface of the endplate facing the annular filter media/core assembly.
 12. A filterassembly as in claim 10, wherein the combination valve comprises anannular member, with the first portion extending outwardly from acentral portion and the second portion extending inwardly from thecentral portion, the second portion being stiffer than the firstportion; the annular filter element engaging the central portion of thecombination valve between the first portion and the second portion toretain the combination valve in place.
 13. A filter assembly as in claim11, wherein the end plate has an inclined portion inclined with respectto the longitudinal axis of the housing and a transverse portiontransverse to the longitudinal axis of the housing, the first inletopening means being disposed in the inclined portion and the secondinlet opening means being disposed at least in part in the transverseportion.
 14. An end plate for use in a filter assembly, said end platehaving first inlet openings, second inlet openings and an outlet openingtherein, said end plate having an inclined portion inclined with respectto the central axis of the end plate and a transverse portion transverseto the central axis of the end plate, the first inlet openings beingdisposed in the inclined portion and the second inlet openings beingdisposed at least in part in the transverse portion.